Nihon Dempa Kogyo Co., Ltd.

Kuichi Kubo

Fumio Asamura

Kozo Ono

Toshiaki Takeuchi

Kunio Hamaguchi

Hiroshi Yoshida

Tsutomu Yamakawa

Noritoshi Kimura

Kouichi Moriya

Takaaki Ishikawa

Yoshinori Narita

Takaharu Fukushima

Katsuyuki Sato

A Geiger-Muller counter tube includes a cylindrical enclosing tube, an anode electrode, a cylindrical cathode electrode, an inert gas, and a quenching gas. The cylindrical enclosing tube has a sealed space. The anode electrode is disposed inside the space and formed in a rod shape. The cylindrical cathode electrode surrounds a peripheral area of the anode electrode inside the space to have an opening. The inert gas and the quenching gas are sealed inside the space. At least one of the anode electrode and the cathode electrode includes a plurality of electrodes inside the enclosing tube.

Geiger-Muller counter tube and radiation measurement apparatus

A Geiger-Muller counter tube includes an enclosing tube, an anode conductor, a cathode conductor, an inert gas, and a quenching gas. The enclosing tube is at least partially cylindrical and has a sealed space. The anode conductor includes an anode electrode and a linear first metal lead portion. The anode electrode is arranged inside the space and formed in a rod shape. The first metal lead portion is connected to the anode electrode and supported at an end of the enclosing tube. The cathode conductor includes a cylindrical cathode electrode and a linear second metal lead portion. The cathode electrode surrounds a peripheral area of the anode electrode inside the space. The second metal lead portion is connected to the cathode electrode and supported at the end of the enclosing tube. The cathode electrode has a side surface through a part of which a through-hole passes.

A radiation measurement apparatus for measuring radiation includes a first and second Geiger-Muller counter tubes and a radiation-direction calculating unit. The first Geiger-Muller counter tube seals an electrode within a circular pipe-shaped enclosing tube that extends in a straight line. The first Geiger-Muller counter tube is arranged along a first direction. The second Geiger-Muller counter tube seals an electrode within a circular pipe-shaped enclosing tube that extends in a straight line. The second Geiger-Muller counter tube is arranged in a second direction intersecting with the first direction. The radiation-direction calculating unit is configured to compare a first detection signal and a second detection signal with one another to calculate a direction of radiation to be emitted from the sample. The first detection signal is output from the electrode of the first Geiger-Muller counter tube. The second detection signal is output from the electrode of the second Geiger-Muller counter tube.

Radiation measurement apparatus

A temperature-compensated crystal oscillator for surface mounting wherein an IC chip into which is integrated a temperature-compensated device having an oscillating circuit and a temperature sensor, which supplies a compensation voltage to a variable-voltage capacitor element of the oscillating circuit, and which also has IC terminals disposed along two edges comprising at least diagonally opposite corner portions of one main surface that acts as a circuit function surface is affixed with the use of bumps to an inner base surface of a main container that is concave in section, and one edge portion of a crystal piece is affixed to an inner wall step portion of the main container; wherein an active element of the oscillating circuit that acts as a heat source and a temperature sensor of the temperature-compensated device are disposed at diagonally opposite corner regions of the IC chip at the greatest distance apart. In addition, IC terminals for thermal dissipation are provided in a central region of the IC chip. The present invention provides a temperature-compensated oscillator for surface mounting in which the temperature-compensation operation at startup is satisfactory and frequency stability is maintained.

Surface mount type temperature-compensated crystal oscillator

A surface-mounted oscillator configured by integrally accommodating an oscillation element, an IC chip, and a circuit element in a surface-mounted package is characterized in that the oscillation element, the IC chip, and the circuit element are arranged in positions in a direction vertical to a mounting surface of the surface-mounted oscillator. The oscillation element may be an oscillation element using bulk wave oscillation, or an oscillation element using surface wave oscillation.

Surface-mounted oscillator

A temperature-compensated crystal oscillator is provided with an IC (integrated circuit) having a power supply terminal, an output terminal, and an automatic frequency control (AFC) voltage input terminal. In the temperature-compensated crystal oscillator, at least one oscillation circuit is integrated and the frequency-temperature characteristic of a quartz crystal unit is compensated. The temperature-compensated crystal oscillator includes one or more damping resistors for reducing the resonance acuteness of parasitic resonance circuits which result from inductance produced when mounting the IC on a wiring board and stray capacitance existing in the vicinity of each terminal of the IC. The dumping resistors are connected to at least one of the power supply terminal, output terminal, and automatic frequency control voltage input terminal.

Temperature-compensated crystal oscillator

A crystal oscillator has a quartz-crystal unit, a first oscillating capacitor connected between a first end of the crystal unit and a reference potential point, a second oscillating capacitor connected between a second end of the crystal unit and the reference potential point, a CMOS inverter connected parallel to the crystal unit, and a feedback resistor connected across the inverter. The crystal oscillator can easily be incorporated into integrated circuits and has an increased variable oscillation frequency range. The crystal oscillator also has an adjustable capacitive assembly having selectable capacitances which is connected parallel to a combined capacitor comprising the first and the second oscillating capacitors.

Crystal oscillator with adjustable capacitive assembly having selectable capacitances

A temperature-compensated crystal oscillator (TCXO) comprises a voltage-controlled crystal oscillator (VCXO) having a crystal unit, a compensating voltage generator for generating a compensating voltage applied to the voltage-controlled crystal oscillator, a low pass filter inserted between the compensating voltage generator and voltage-controlled crystal oscillator, and a switching element connected in parallel with the low pass filter for short-circuiting across the low pass filter. In a manufacturing process of the temperature-compensated crystal oscillator, switching element is brought into a conducting state when an excitation electrode of the crystal unit is irradiated with an ion beam for adjusting the oscillation frequency.

A temperature-compensated crystal oscillator with good phase noise characteristics has a crystal unit, a voltage-variable capacitive element inserted in a closed oscillating loop including the crystal unit, and an amplifier for keeping oscillation in the closed oscillating loop. The frequency vs. temperature characteristics of the temperature-compensated crystal oscillator can be compensated for by the temperature compensating voltage input thereto. The temperature compensating voltage is applied to an anode of the voltage-variable capacitive element, and a voltage to prevent a current from flowing through the voltage-variable capacitive element is applied to a cathode of the voltage-variable capacitive element. The voltage-variable capacitive element preferably comprises a variable-capacitance diode.

A surface mounting quartz crystal oscillator has an IC chip containing an oscillator circuit, and a quartz crystal unit which are sealed in a container body by a metal cover, wherein stray capacitances C C are equivalently in parallel with oscillation capacitors Ca, Cb connected to one and the other ends of the crystal unit, respectively. A gap between the IC chip and a crystal blank of the crystal unit, and a gap between the crystal blank and metal cover are set in accordance with a changing amount of the oscillation frequency due to a change in the stray capacitances C C in a direction in which a change in equivalent series capacitance is reduced, as viewed from the crystal unit, while maintaining a spacing between the IC chip and metal cover.

Surface mounting crystal oscillator

A quartz-crystal oscillator comprises an oscillating stage and a buffering stage. The oscillating stage has a resonance circuit including a quartz-crystal unit and a capacitor, and an inverting amplifier amplifying a resonance frequency component of the resonance circuit due to feedback oscillation. The buffering stage is provided for outputting the output of the oscillating stage by reducing the amplitude thereof, and has first and second MOS FETs of the same conductive type arranged in series between a power supply and a reference potential. A signal at the output terminal of the inverting amplifier is impressed to the gate of the first MOS FET, a signal at the input terminal of the inverting amplifier is impressed to the gate of the second MOS FET, and an output signal is obtained from a connecting point of the first and second MOS FETs.

Crystal oscillator

A voltage-controlled oscillator (VCO) using a transistor, capable of-using a capacitor for DC blocking with small capacitance and achieving a large amount of change in the oscillating frequency. The voltage-controlled oscillator comprises a transistor for oscillation and amplification, first and second nodes, a quartz-crystal element inserted between the first and second nodes, a first capacitor connecting the first node with a base of the transistor, a second capacitor connecting the second node with a collector of the transistor, a first variable capacitance diode connected to the first node, a second variable capacitance diode connected to the second node, and means for applying a control voltage to the first and second variable capacitance diodes.

Voltage-controlled oscillator

A digital temperture compensation oscillator for digitally compensating a variation in oscillation frequency due to temperatures, by applying a compensation voltage to a voltage controlled oscillator, comprises temperature detection means, A/D conversion means, memory means, operation means and D/A conversion means. The temperature detection means detects temperatures when the voltage controlled oscillator is operated, and generates a temperature signal. The A/D conversion means receives the temperature signal, digitizes the temperature signal, and generates digital temperature data. The memory means stores compensation data corresponding to the compensation voltage as difference data at corresponding addresses. The difference data includes, when N-stage level difference data (N=a positive integer) are utilized, predetermined reference values of 0th difference data to (N-1)-th difference data of the compensation data and all N-th difference data. The operation means receives the digital temperature data and the difference data, and generates the compensation data on the basis of the difference data in response to the digital temperature data. The D/A conversion means receives the compensation data, converts the compensation data into an analog compensation voltage, and supplies the analog compensation voltage to the voltage controlled oscillator.

Digital temperature compensation oscillator

A digital temperature-compensated oscillator comprises a crystal oscillator, a first memory previously storing digital temperature compensation data obtained by previously measuring the relation between the ambient temperatures and the frequency deviations of the crystal oscillator, a second memory for storing frequency offset amounts of the oscillation frequency of the crystal oscillator, a temperature sensor for outputting analog detection data relating to the ambient temperature, an A/D converter for converting the analog detection data to digital detection data, a readout circuit for reading out temperature compensation data corresponding to the digital detection data and stored in the first memory according to the digital detection data and reading out the frequency offset amount stored in the second memory according to the digital detection data, an operation circuit for effecting the following calculation by use of the readout temperature compensation data and readout frequency offset amount to derive digital control voltage,

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Saitama, Japan

Kuichi Kubo